Hi Melos, you're right about the warmups. Uncomfortable suggests randomly picking 2-3 exercises from your completed lessons to do as a warmup for 10-15 minutes, if you feel like you struggle with the branches you can add those to your warmups more often, but don't neglect the other exercises that you've tackled in the previous lessons. https://drawabox.com/lesson/0/3/warmups

What I mean with tackling dirt as a texture is to make it more implicit. Since dirt is composed of tiny little pebbles, drawing them out can be quite tedious and will distract people from the plant. You can take a look at how Uncomfortable draws dirt as a texture in the following example homework: (upper middle sausage) https://drawabox.com/lesson/2/7/example

He doesn't draw every detail, and instead focuses on hinting at the texture by drawing the cast shadows of a few of the pebbles. That way, the dirt doesn't become the focal point (the point that the viewer will first look at).

I hope this helps! Have a nice day.